Rob Kardashian Has Lost About 30-50 Pounds: 'His Life Is Completely Different Now' (Exclusive)

Rob Kardashian has been making big strides in terms of both his health and his relationship with his famous family, a source tells ET.

The 31-year-old reality star, who has largely remained out of the spotlight since his very public split from ex-fiancee Blac Chyna last July, has lost a significant amount of weight, our source says. Aside from the weight loss -- which the source estimates to be around 30-50 pounds -- the source notes that Rob has been working hard to get his life back on track, especially for the sake of his 1-year-old daughter, Dream.

“Getting out of the spotlight was so important for Rob,” the source says, noting that quitting Instagram has also been especially good for him. “He needed to completely change his life, things were spiraling out of control for him and his health and relationships were suffering. He needed to refocus.”

“His life is completely different now," the source adds.

According to the source, although Rob was in a dark place this time last year, his outlook has changed significantly thanks to mending his co-parenting relationship with Chyna, as well as getting his health under control by working with professionals and exercising and eating well.

“He’s got his priorities in check," the source says. "First and foremost he is there for Dream and he knows that to do so he needs to be healthy."

The source adds that while there was a time when Rob barely left his home, he’s now been seen out a lot more and appears to be happy and in good spirits. According to the source, Rob has been spending a lot of time with his sisters -- Kim, Khloe and Kourtney Kardashian, as well as Kendall and Kylie Jenner -- and with their children.

“All the cousins [Dream and Rob’s sister’s kids] are very close,” the source says.

Earlier this month, Khloe hosted a "cousin cupcake party" for her daughter True's 6-month birthday, which included Dream. The priceless group photo also included Kylie's 8-month-old daughter, Stormi, and Kim's youngest kids, 2-year-old Saint and 9-month old Chicago.